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Blue-green Algae a Concern for Livestock

AMES, Iowa ― Already this summer there have been reports of blue-green algae blooms in Iowa ponds, prompting farmers to pay close attention to grazing and water resource location for their livestock.

Blue-green algae are commonly found in Iowa lakes, ponds, rivers and streams during summer and autumn, and can form dense algal blooms that resemble mats on the water surface. These blooms can be stimulated following storms or heavy rainfall when surface runoff containing phosphorus and nitrogen enters the water. The blooms can be quite bad when storm events are followed by prolonged periods of hot temperatures.

“Because blue-green algae can produce poisonous neurotoxins and hepatoxins, they also are a potential health concern to livestock, pets, wildlife and humans, and can be fatal if consumed,” said Steve Ensley, Iowa State veterinary diagnostic and production animal medicine clinician.

Ensley and Chris Filstrup, of the Iowa State Limnology Laboratory, explain how to recognize blue-green algae in a one-page fact sheet they have written. The fact sheet also describes potential toxic effects of the algae, proper sampling methods for testing and suggests ways to reduce the incidence of blooms in lakes and ponds.

The Limnology Lab focuses on research and analyses of aquatic ecology in the Midwest, and offers a variety of tests and information on water-based information and resources.